Wave powered pumping apparatus

ABSTRACT

An apparatus is disclosed for an improved float type wave powered pump that uses the continuous rising and falling wave action in a body of water to pump a fluid. The pump includes piston and cylinder assemblies that are configured for relative reciprocal movement therebetween. One of the assemblies is anchored to the floor of the body of water and the other is vertically moveable in response to a drive float riding on a wave. The pump selectively includes a tide compensating device to reduce the ratio of vertical travel of the drive float to vertical travel of the moveable assembly. The pump also selectively includes a fluid inlet check valve incorporating a support plate of the piston assembly with openings therein and a cover for the same. The pump further selectively includes a directional pressure-activated seal at the point of sliding connection between the piston rod and the cylinder.

BACKGROUND

1. Field

Embodiments of the present invention relate generally to float type wavepowered pumping devices that use the continuous rising and falling waveaction in a body of water to pump a fluid.

2. Discussion of the Prior Art

Those of ordinary skill in the art will appreciate that conventionalwave powered pumps are typically used in large bodies of water, such asthe ocean or the sea, where the operating environment often dictatesthat the pumps are working in an unsupervised state for long periods oftime. Those of ordinary skill in the art will also appreciate that it isdesirable for such wave powered pumps to move large quantities of fluidin order to be most productive. Conventionally, large and complex pumpsare used in an effort to meet these demands. While this typicalconstruction has been satisfactory in some respects, the complexity ofthe pumps reduces their appeal and often introduces inefficiencies intothe system due to the amount of components involved. Additionally,conventional wave powered pumps suffer from durability issues as many ofthe components are prone to fail by component breakage or deformation inthe unsupervised operation state in the ocean.

SUMMARY

According to one aspect of the present invention, an apparatus isprovided for pumping a fluid using the continuous rising and fallingwave action in a body of water, the apparatus including a cylinderassembly, a piston assembly, an anchor, a drive float, and a tidecompensating device. The piston assembly is operably coupled with thecylinder assembly to define an expandable chamber, a fluid inletcommunicating with the chamber, and a fluid outlet communicating withthe chamber, wherein fluid is drawn into the chamber through the inletas the chamber expands and fluid is pumped out of the chamber throughthe outlet as the chamber contracts. The anchor is connected to ananchored one of said cylinder and piston assemblies to position saidanchored one of the assemblies below the surface of the body of waterand to restrict upward movement of said anchored one of the assemblies.The drive float rides on top of the body of water such that a risingwave lifts the drive float upward and a falling wave lowers the drivefloat downward. The drive float is coupled to a relatively moveable oneof said cylinder and piston assemblies to move the same in an upwarddirection relative to the anchored one of the assemblies in response toa rising wave lifting the drive float. The piston and cylinderassemblies are interconnected so that the chamber contracts, to therebypump fluid from the chamber through the outlet, during upward movementof the moveable one of the assemblies, and the chamber expands, tothereby draw fluid into the chamber through the inlet, during downwardmovement of the moveable one of the assemblies. Finally, the tidecompensating device interconnects the drive float and moveable one ofthe assemblies in such a manner that the amount of upward movement ofthe moveable one of the assemblies is relatively less than the amount ofupward movement of the drive float in response to a rising wave liftingthe drive float.

Another aspect of the present invention concerns an apparatus forpumping a fluid using the continuous rising and falling wave action in abody of water, the apparatus including a cylinder assembly, a pistonassembly, an anchor, and a drive float. The piston assembly is operablycoupled with the cylinder assembly to define an expandable chamber, afluid inlet communicating with the chamber, and a fluid outletcommunicating with the chamber, wherein fluid is drawn into the chamberthrough the inlet as the chamber expands and fluid is pumped out of thechamber through the outlet as the chamber contracts. The anchor isconnected to an anchored one of said cylinder and piston assemblies toposition said anchored one of the assemblies below the surface of thebody of water and to restrict upward movement of said anchored one ofthe assemblies. The drive float rides on top of the body of water suchthat a rising wave lifts the drive float upward and a falling wavelowers the drive float downward. The drive float is coupled to arelatively moveable one of said cylinder and piston assemblies to movethe same in an upward direction relative to the anchored one of theassemblies in response to a rising wave lifting the drive float. Thepiston and cylinder assemblies are interconnected so that the chambercontracts, to thereby pump fluid from the chamber through the outlet,during upward movement of the moveable one of the assemblies, and thechamber expands, to thereby draw fluid into the chamber through theinlet, during downward movement of the moveable one of the assemblies.The piston assembly includes a piston rod slidably coupled to thecylinder assembly to permit generally vertical relative movementtherebetween. The cylinder assembly includes an alignment guide thatdefines in part the chamber and a central pathway. The piston rod isslidably received within the pathway. The alignment guide includes apressure-activated seal around the pathway. The pressure-activated sealimparts approximately no drag against the piston rod when the moveableone of the assemblies moves downwardly. Finally, the pressure-activatedseal is put under pressure against the piston rod as the moveable one ofthe assemblies moves upwardly to expel the fluid out of the cylinder,such pressure preventing fluid from exiting the chamber through thepathway.

Yet another aspect of the present invention concerns an apparatus forpumping a fluid using the continuous rising and falling wave action in abody of water, the apparatus including a cylinder assembly, a pistonassembly, an anchor, and a drive float. The piston assembly is operablycoupled with the cylinder assembly to define an expandable chamber, afluid inlet communicating with the chamber, and a fluid outletcommunicating with the chamber, wherein fluid is drawn into the chamberthrough the inlet as the chamber expands and fluid is pumped out of thechamber through the outlet as the chamber contracts. The fluid inletincludes a check valve permitting one-way fluid flow into the chamberthrough the inlet. The anchor is connected to an anchored one of saidcylinder and piston assemblies to position said anchored one of theassemblies below the surface of the body of water and to restrict upwardmovement of said anchored one of the assemblies. The drive float rideson top of the body of water such that a rising wave lifts the drivefloat upward and a falling wave lowers the drive float downward. Thedrive float is coupled to a relatively moveable one of said cylinder andpiston assemblies to move the same in an upward direction relative tothe anchored one of the assemblies in response to a rising wave liftingthe drive float. The piston and cylinder assemblies are interconnectedso that the chamber contracts, to thereby pump fluid from the chamberthrough the outlet, during upward movement of the moveable one of theassemblies, and the chamber expands, to thereby draw fluid into thechamber through the inlet, during downward movement of the moveable oneof the assemblies. The piston assembly includes a rigid support platehaving a chamber-defining surface that defines in part the chamber. Thesupport plate presents a plurality of openings that permit fluid to passthrough the support plate and into the chamber. The piston assemblyfurther includes a generally fluid impermeable cover shiftably disposedadjacent the support plate for movement into and out of a plate-sealingposition, in which the plate sealingly engages the chamber-definingsurface and thereby prevents fluid flow through the plate. Thus, thesupport plate and cover cooperatively form the fluid inlet check valve.

This summary is provided to introduce a selection of concepts in asimplified form that are further described below in the detaileddescription of the preferred embodiments. This summary is not intendedto identify key features or essential features of the claimed subjectmatter, nor is it intended to be used to limit the scope of the claimedsubject matter.

Various other aspects and advantages of the present invention will beapparent from the following detailed description of the preferredembodiments and the accompanying drawing figures.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

A preferred embodiment of the present invention is described in detailbelow with reference to the attached drawing figures, wherein:

FIG. 1 is a reduced, environmental, partially schematic view of aplurality of wave powered pumping apparatuses, each constructed inaccordance with the principles of a preferred embodiment of the presentinvention, the pumping apparatuses shown in a body of water and in fluidcommunication with a reservoir for holding pumped fluid;

FIG. 2 is an elevation view of a wave powered pumping apparatusconstructed in accordance with the principles of a preferred embodimentof the present invention;

FIG. 3 is a partial side sectional view of the wave powered pumpingapparatus shown in FIG. 2, particularly illustrating the structure andfunction of the components thereof, including a piston within a cylinderand a tide compensating device depicted in a pump reloaded position,with broken line arrows indicating the direction of flow of a fluid andsolid, thick arrows indicating prospective movement of the next stage ofoperation of the apparatus;

FIG. 4 is a partial side sectional view of the wave powered pumpingapparatus, similar to that of FIG. 3, but with the piston within thecylinder and the tide compensating device in a fluid expelling position,with broken line arrows indicating the direction of flow of a fluid andsolid, thick arrows indicating prospective movement of the next stage ofoperation of the apparatus;

FIG. 5 is an enlarged, top sectional view of a portion of the wavepowered pumping apparatus, the view taken along the line 5-5 of FIG. 2,particularly illustrating in detail a frame top plate secured to aframework of the tide compensating device, and depicting springs of apump reload mechanism and a fluid outlet conduit;

FIG. 6 is an enlarged, fragmentary side sectional view of a top portionof the wave powered pumping apparatus in the position shown in FIG. 4,particularly illustrating in detail the tide compensating device,including part of a framework, a rotatable pulley at the top of thepiston, and a cable fixed to the top of the framework and wrapped aroundthe pulley;

FIG. 7 is a partial side sectional view of the wave powered pumpingapparatus, similar to that of FIG. 4, but with the piston within thecylinder and the tide compensating device depicted in a position movingfrom a fluid expelling position to a pump reloaded position, with brokenline arrows indicating the direction of flow of a fluid and solid, thickarrows indicating prospective movement of the next stage of operation ofthe apparatus;

FIG. 8 is an enlarged, top sectional view of a portion of the wavepowered pumping apparatus, the view taken along the line 8-8 of FIG. 2,particularly illustrating in detail a rigid support plate of the pistonwith a plurality of openings therein disposed within the cylinder;

FIG. 9 is an enlarged, fragmentary side sectional view of a bottomportion of the wave powered pumping apparatus in the position shown inFIG. 3, particularly illustrating in detail a cylinder bottom platesecured to the framework of the tide compensating device, and the pistonwith a cover and stopper cooperating to form a fluid inlet check valve;

FIG. 10 is an enlarged, fragmentary side sectional view of anintermediate portion of the wave powered pumping apparatus in theposition shown in FIG. 3, particularly illustrating in detail a cylindertop plate secured to the framework of the tide compensating device atthe top of the cylinder forming an alignment guide, including a pathwayfor the piston rod, and a pressure-activated seal around the pathway;

FIG. 11 is a partial side sectional view of an alternative wave poweredpumping apparatus constructed in accordance with the principles of asecond embodiment of the present invention, similar in many respects tothe wave powered pumping apparatus shown in FIG. 3, but depicting a tidecompensating device in a pump reload position with additional rotatingpulleys to further reduce the ratio of vertical travel of a float tovertical travel of the piston, with broken line arrows indicating thedirection of flow of a fluid and solid, thick arrows indicatingprospective movement of the next stage of operation of the apparatus;

FIG. 12 is a partial side sectional view of the alternative wave poweredpumping apparatus of FIG. 11 and similar to the view of the same, butwith the piston within the cylinder and the tide compensating device ina fluid expelling position, depicting the reduction of vertical travelof the piston relative to the float, again with broken line arrowsindicating the direction of flow of a fluid and solid, thick arrowsindicating prospective movement of the next stage of operation of theapparatus;

FIG. 13 is a partial side sectional view of an alternative wave poweredpumping apparatus, constructed in accordance with the principles of athird embodiment of the present invention, similar in some respects tothe wave powered pumping apparatus shown in FIG. 3, but depicting apiston assembly as an anchored element and a cylinder assembly as amoveable element driven upward by movement of a drive float, and a pumpreload mechanism including a submerged float, tether, and pulleys tobias the apparatus in a pump reload position, with broken line arrowsindicating the direction of flow of a fluid and solid, thick arrowsindicating prospective movement of the next stage of operation of theapparatus; and

FIG. 14 is a partial side sectional view of the alternative wave poweredpumping apparatus of FIG. 13 and similar to the view of the same, butwith the cylinder in a fluid expelling position, depicting movement ofthe submerged float where the bias of the apparatus in a pump reloadposition has been overcome by the upward force of the drive float on arising wave, again with broken line arrows indicating the direction offlow of a fluid and solid, thick arrows indicating prospective movementof the next stage of operation of the apparatus.

The drawing figures do not limit the present invention to the specificembodiments disclosed and described herein. The drawings are notnecessarily to scale, emphasis instead being placed upon clearlyillustrating the principles of the preferred embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is susceptible of embodiment in many differentforms. While the drawings illustrate, and the specification describes,certain preferred embodiments of the invention, it is to be understoodthat such disclosure is by way of example only. There is no intent tolimit the principles of the present invention to the particulardisclosed embodiments.

The present invention provides an improved float type wave powered pumpthat uses the continuous rising and falling wave action in a body ofwater to pump a fluid. The pump includes a piston assembly and acylinder assembly configured for relative reciprocal movementtherebetween. One of the assemblies is anchored to the floor and theother is vertically moveable in response to a drive float riding on awave. Embodiments of the present invention provide a tide compensatingdevice to reduce the ratio of vertical travel of the moveable assemblyrelative to vertical travel of the drive float. Embodiments of thepresent invention also provide a fluid inlet check valve incorporating arigid support plate of the piston assembly with openings therein and ashiftable cover for the same to quickly reload fluid in the cylinder.Embodiments of the present invention further provide a directionalpressure-activated seal at the point of sliding connection between thepiston rod and the cylinder.

With initial reference to FIG. 1, a wave powered energy generatingsystem 20 selected for purposes of illustration combines a plurality ofwave powered pumping apparatuses 22 and a fluid powered generatingsystem 24. Each wave powered pumping apparatus 22 is disposed in a bodyof water 26. The body of water 26 extends vertically between a solidbottom surface 28 underneath the body of water 26 and a top surface 30of the body of water 26. The top surface 30 moves up and down as a wave32 moves across the surface top 30, as will be readily appreciated byone of ordinary skill in the art. The continuous nature of wave movementin a body of water produces a continuous change in the height of the topsurface 30 of the water as a passing wave 32 moves the top surface 30 upto a crest 34, down to a trough 36, and so on, as is generally known inthe art.

It is noted initially, that the environment setting depicted in FIG. 1is provided as a contextual example only, and that the wave poweredpumping apparatus of the present invention could alternatively be usedin other conditions, as will be appreciated by one of ordinary skill inthe art. For example, a wave powered pumping apparatus 22 couldalternatively be used to provide high pressure seawater, even in excessof 800-1000 psi, to a desalinization system (not shown) or to a systemfor the production of hydrogen (not shown), in either gas or liquidform.

Each wave powered pumping apparatus 22 broadly includes a cylinderassembly 38 and a piston assembly 40, as will be discussed in greaterdetail below. In the illustrated embodiment, the cylinder assembly 38 isfixedly connected to an anchor 42 and the anchor 42 is disposed on thebottom surface 28 underneath the body of water 26. Also in theillustrated embodiment, the piston assembly 40 is moveably connected toa drive float 44 and the drive float 44 is disposed on the top surface30 of the body of water 26. The cylinder assembly 38 and the pistonassembly 40 cooperate to define an expandable chamber 37. The chamber 37is configured to contain a working fluid 46 that is drawn into thechamber 37 upon expansion of the chamber 37 and is expelled out of thechamber 37 upon contraction of the chamber 37.

As depicted, the wave powered pumping apparatus 22 pumps the fluid 46out of an outlet 48 in the cylinder assembly 38. In the illustratedembodiment, the fluid 46 pumped by the wave powered pumping apparatus 22is the same as the body of water 26, although the wave powered pumpingapparatus 22 could alternatively pump a different fluid through aclosed-loop system without departing from the teachings of the presentinvention. The fluid 46 is pumped through the outlet 48 into to aconduit 50. In the illustrated embodiment, the conduits 50 of each wavepowered pumping apparatus 22 converge into a main passage 52. It isnoted, however, that in an alternative embodiment, each conduit 50 couldextend individually, rather than converging into the main passage 52,without departing from the teachings of the present invention.

The main passage 52 transports the pumped fluid 46 to a reservoir 54that holds the pumped fluid 46. The fluid 46 in the reservoir 54 iscontrollably released from a reservoir outlet 56 to power ahydroelectric generator 58 to produce useful energy, such aselectricity. The fluid 46 then passes from the generator 58 to adischarge 60, where it is released through a discharge outlet 62. In theillustrated embodiment, the pumped fluid 46 is the same substance as thebody of water 26 and the reservoir 54 is disposed at a locationvertically above the top surface 30 of the body of water 26. Thus, asdepicted in FIG. 1, the main passage 52 carries the pumped fluid 46vertically upward to the reservoir 54. A check valve 60 in the mainpassage 52 prevents the pumped fluid 46 from flowing vertically downward(as motivated by gravity) back to the wave powered pumping apparatus 22.Also, as the pumped fluid 46 is the same substance as the body of water26, the pumped fluid 46 is released from the discharge outlet 62 intothe body of water 26, the discharge flow being motivated by gravity.

It will be recognized that the principles of the present invention arenot limited to use with the particular power generating system 24illustrated in FIG. 1. It will be appreciated by one of ordinary skillin the art that the exemplary power generating system could take otherforms without departing from the teachings of the present invention. Forexample, the wave powered pumping apparatus 22 could be used to pump afluid other than that of the body of water 26, such other working fluidbeing moved through a closed-loop system. It is also within the ambit ofthe present invention to pump the fluid to a location other than areservoir disposed vertically higher than the body of water, as theheight of the pumped fluid in the illustrated embodiment is used toallow gravitational pressure acting on the fluid released from thereservoir 54 to turn the generator 58. The wave powered pumpingapparatus 22 could alternatively be used to pump fluid to anotherlocation and still use gravitational pressure acting on the fluidreleased from a reservoir, provided only that a discharge outlet fromthe reservoir is disposed at a location vertically below the reservoiroutlet. It is also noted that various general aspects of powergeneration from wave powered pumps are described in U.S. Pat. Nos.4,754,157 and 4,883,411 by the same inventor as the present invention,the disclosures of which are hereby incorporated by reference herein. Itis further noted that the wave powered pumping apparatus 22 couldalternatively be used in systems other than power generation, such asproviding high pressure seawater for a desalinization system or ahydrogen production system, as discussed above.

Turning now to FIGS. 2-10, the wave powered pumping apparatus 22 broadlyincludes the cylinder assembly 38 and the piston assembly 40. The pistonassembly 40 is configured for relative reciprocal movement within thecylinder assembly 38, as discussed briefly above, and the assemblies arecoupled to define the chamber 37. In the illustrated embodiment, thecylinder assembly 38 is connected to the anchor 42, and the pistonassembly 40 is connected to the drive float 44 through a tidecompensating device 66, although it is clearly within the ambit of thepresent invention to reverse this orientation (such that a pistonassembly is connected to an anchor, and a cylinder assembly is connectedto a drive float). It is noted that such a configuration, which canimprove pumping efficiency, is illustrated in FIGS. 13 and 14 and isdiscussed in greater detail below. The tide compensating device 66 isconfigured to reduce the amount of upward vertical movement of thepiston assembly 40 relative to the amount of upward vertical movement ofthe drive float 44 as the drive float 44 moves upward in response to arising wave crest 34 lifting the drive float 44, as will be discussed inmore detail below. The drive float 44 is preferably, although notnecessarily constructed out of dense foam or similar buoyant materialand shaped generally in the form of a disc, as will be readilyappreciated by one of ordinary skill in the art.

With particular reference to FIGS. 2 and 3, the cylinder assembly 38 ofthe illustrated embodiment includes a circular body 68 made of a sectionof PVC pipe or similar material. It will be appreciated by one ofordinary skill in the art that the cylinder body 68 could also takeother shapes (e.g., polygonal in cross-section), or be made from othermaterials, without departing from the teachings of the presentinvention. It is noted that references to upper and lower or top andbottom refer to general relative vertical orientation of components asviewed from the vantage point of FIG. 1, corresponding to the typicalorientation of the wave powered pumping apparatus 22 disposed in thebody of water 26 for operation therein, as will be readily appreciatedby one of ordinary skill in the art. This general orientation remainsconstant throughout the present detailed description to provideconsistency in referring to components of the present invention.

A cylinder bottom plate 70 is fixed to the lowermost end of the cylinderbody 68 and forms a bottom thereto. The cylinder bottom plate 70includes a central hole 72 and a plurality of radially extendingopenings 74. The openings 74 allow the fluid 46 of the body of water 26to flow through the cylinder bottom plate 70. Similarly, a cylinder topplate 76 is fixed to the uppermost end of the cylinder body 68 and formsa top thereto. The cylinder top plate 76 includes a central hole 78 anda plurality of radially extending openings 80. The openings 80 allow thefluid 46 of the body of water 26 to flow through the cylinder top plate76. In the illustrated embodiment, the cylinder bottom plate 70 and thecylinder top plate 76 are the same size and shape for ease ofmanufacture, although such conformity is not necessary. A shiftablesealing element 82 is disposed below and generally coaxial with thecylinder top plate 76. The shiftable sealing element 82 is preferably,although not necessarily, made of leather or other tough, flexiblematerial (such as elastomer), as will be appreciated by one or ordinaryskill in the art. The shiftable sealing element 82 is attached to thecylinder top plate 76 with a plurality of fasteners 83, as illustratedin detail in FIG. 10. The portion of the sealing element 82 disposedradially outward of the fasteners 83 seals the openings 80 in thecylinder top plate 76 during pumping operation of the wave poweredpumping apparatus 22, as will be discussed in greater detail below. Theportion of the shiftable sealing element 82 disposed radially inward ofthe fasteners 83 is directed away from the central hole 78 in thecylinder top plate 76 to form a directional pressure-activated seal 85,as will be explained in greater detail below.

The cylinder assembly 38 includes the outlet 48, discussed brieflyabove, that allows the pumped fluid 46 to be expelled out of thecylinder assembly 38 and into the conduit 50 during pumping operation ofthe wave powered pumping apparatus 22. The conduit 50 includes an outletcheck valve 84 that allows the pumped fluid 46 to exit the cylinderassembly 38 through the outlet 48, but not flow back into the cylinderassembly 38, as will be understood by one of ordinary skill in the art.The cylinder assembly 38 is connected to the anchor 42 with a chain 86.The chain 86 extends from the anchor 42 and is connected to a pair ofeyelet fasteners 88, as depicted in greater detail in FIG. 9. Eacheyelet fastener 88 is attached to the cylinder bottom plate 70 torestrict vertical movement of the cylinder assembly 38.

With continued reference to FIGS. 2 and 3, the piston assembly 40 of theillustrated embodiment includes an elongated piston rod 90 disposed ingeneral axial alignment with the cylinder body 68. The piston rod 90extends generally vertically lengthwise through a length of the cylinderassembly 38. At least a portion of the piston rod 90 extends sealablyout of the top of the cylinder assembly 38 through the central hole 78in the cylinder top plate 76, with the central hole 78 serving as analignment guide for movement of the piston rod 90. Additional details ofthe interaction between the piston rod 90 and the cylinder top plate 76will be discussed more thoroughly below.

The piston assembly 40 also includes a rigid support plate 92 fixed atthe lower end of the piston rod 90. The rigid support plate 92 includesa central hole 94 and a plurality of radially extending openings 96, asdepicted in detail in FIG. 8. The openings 96 allow the fluid 46 of thebody of water 26 to flow through the rigid support plate 92. The rigidsupport plate 92 is attached to a threaded lower end 98 of the pistonrod 90. A nut 100 is tightened on the threaded lower end 98 of thepiston rod 90, below the rigid support plate 92, to fixedly connect therigid support plate 92 to the piston rod, as depicted in detail in FIG.9. A piston side seal 102 extends from the bottom of the rigid supportplate 92 and around the sides of the rigid support plate 92 to form agenerally fluid impermeable seal against the inside walls of thecylinder body 68. The piston side seal 102 is attached to the rigidsupport plate 92 by inserting a plurality of fasteners 104 through thepiston side seal 102 and into holes 106 in the rigid support plate 92,as depicted in FIGS. 8 and 9.

A flexible flapper 108 is disposed above the rigid support plate 92 andis generally coaxial with the same. The flexible flapper 108 ispreferably, although not necessarily, made of leather or other tough,flexible material (such as elastomer), as will be appreciated by one orordinary skill in the art. In the illustrated embodiment, the flexibleflapper 108 is made of the same leather material as the shiftablesealing element 82 for ease of manufacture. The flexible flapper 108 ismade of a generally fluid impermeable material such that, when theflexible flapper 108 is pressed downward against the rigid support plate92, the fluid 46 in the chamber 37 does not flow out of the plurality ofopenings 98 in the rigid support plate 92. The flexible flapper 108 canshift out of the way of the plurality of openings 98 in the rigidsupport plate 92 when the flexible flapper 108 is not pressed downwardagainst the rigid support plate 92. During such shifting, the fluid 46of the body of water 26 can flow through the plurality of openings 98 inthe rigid support plate 92 and into the chamber 37, as will be discussedin greater detail below.

A stopper 110 is attached to the piston rod 90 at a location axiallyabove the flexible flapper 108. A fastener 112, such as a bolt, connectsthe stopper 110 to the piston rod 90. The stopper 110 prevents theflexible flapper 108 from shifting axially upward along the piston rod90 past the position of the stopper 110. The stopper 110 also maintainsthe central portion of the flexible flapper 108 nearest the piston rod90 in generally close proximity to the rigid support plate 92.

Returning now to FIGS. 2 and 3, a piston reloading mechanism 114 isdepicted for biasing the piston in the downward, or reload, position,the significance of which will be discussed in more detail in theoperation description below. A lower spring support 116 is fixed to thetop of the cylinder bottom plate 70. The lower spring support 116includes opposed ends 118 and 120 that extend radially outward to adisposition outside of the cylinder body 68. Similarly, an upper springsupport 122 is disposed above the top of the cylinder top plate 76 andis connected to the upper end of the piston rod 90 for movementtherewith. The upper spring support 122 includes opposed ends 124 and126 that extend radially outward to a disposition outside of thecylinder body 68. In the illustrated embodiment, the lower springsupport 116 and the upper spring support 122 are the same size and shapefor ease of manufacture, although such conformity is not necessary.

A pair of springs 128 and 130 extend between the lower spring support116 and the upper spring support 122 on the outside of the cylinder body68. More specifically, an extension spring 128 extends generallyparallel to the axis of the cylinder body 68 from a connection at theend 118 of the lower spring support 116 to a connection at the end 124of the upper spring support 122. Similarly, an extension spring 130extends generally parallel to the axis of the cylinder body 68 from aconnection at the end 120 of the lower spring support 116 to aconnection at the end 126 of the upper spring support 122.

In brief, the piston reloading mechanism 114 provides a downward forceto bias the piston assembly 40 in the downward direction, with suchdownward force being overcome by an upward force as the piston assembly40 moves upward to expel fluid out of the chamber 37. The springs 128and 130 preferably, although not necessarily, collectively provide adownward bias force that is approximately ten to twenty percent of theupward buoyant force created by the drive float 44. The downward biasforce provided by the springs 128 and 130 can be changed by usingalternative springs having a different spring constant, as will beunderstood by one of ordinary skill in the art. In the absence of anupward force, the piston reloading mechanism 114 return the pistonassembly 40 back to the downward position following the fluid expulsion,as will be readily appreciated by one of ordinary skill in the art.

It is noted that it is within the ambit of the present invention for thepiston reloading mechanism 114 to alternatively comprise anotherconstruction, such as a weight and tether. It is further noted that thepiston reloading mechanism 114 cooperates with the drive float 44 toprovide and maintain a controlled motion of the piston assembly 40. Thiscontrolled motion of the piston assembly 40 makes the wave poweredpumping apparatus 22 essentially storm resistant. Specifically, theillustrated configuration is particularly useful in eliminatingso-called “hammering” of the apparatus, which would otherwise occur inoceanic storms, as will be appreciated by one of ordinary skill in theart.

With continued reference to FIGS. 2 and 3, the tide compensating device66 interconnects the drive float 44 and the piston assembly 40 such thatthe amount of upward movement of the piston assembly 40 is relativelyless than the amount of upward movement of the drive float 44 as thedrive float 44 moves upward in response to a rising wave crest 34lifting the drive float 44, as will be discussed in more detail below.As depicted, the tide compensating device 66 includes a framework 132that extends generally parallel to the axis of the cylinder body 68 andis disposed on the outside of the cylinder body 68. The framework 132includes a first pair of frame members 134 and 136 disposed on one sideof the cylinder body 68 and a second pair of frame members 138 and 140disposed on another side of the cylinder body 68, as depictedparticularly in the top down sectional view of FIG. 5. In theillustrated embodiment, each of the frame members 134, 136, 138, and 140have the same height, the height being approximately twice that of theheight of the cylinder body 68. The frame members 134, 136, 138, and 140are disposed in alignment with the cylinder bottom plate 70 and extendupwardly along the sides of the cylinder body 68 to a top portion abovethe cylinder top plate 76.

The frame members 134, 136, 138, and 140 are connected at the topportion with a frame top plate 142. The frame top plate 142 is fixed tothe uppermost ends of the frame members 134, 136, 138, and 140 and formsa top thereto. The frame top plate 142 includes a central hole 144 and aplurality of radially extending openings 146. The openings 146 allow thefluid 46 of the body of water 26 to flow through the frame top plate142. In the illustrated embodiment, the frame top plate 142 is the samesize and shape as the cylinder bottom plate 70 and the cylinder topplate 76 for ease of manufacture, although such conformity is notnecessary.

As depicted in FIG. 5, the frame members 134, 136, 138, and 140 areconnected to the frame top plate 142 with spacers 148 and 150 andfasteners 152 and 154, as will be readily understood by one of ordinaryskill in the art. Similarly, the frame members 134, 136, 138, and 140are also connected to the cylinder top plate 76 and the cylinder bottomplate 70 with similar spacers 156 and 158 and fasteners (not shown), asdepicted generally in FIG. 8. The positioning of the pair of framemembers 134 and 136 presents a vertical slot 160 between the framemembers 134 and 136. Similarly, the positioning of the pair of framemembers 138 and 140 presents a vertical slot 162 between the framemembers 138 and 140. These slots 160 and 162 provide alignment paths forthe vertical travel of the upper spring support 122, as depicted inFIGS. 5 and 8. It will be appreciated by one of ordinary skill in theart that these slots 160 and 162 maintain the upper spring support 122in general alignment with the lower spring support 116 while the upperspring support 122 moves up and down during operation of the wavepowered pumping apparatus 22.

A pulley 164 is disposed above the top of the upper spring support 122and is housed in a bracket 166 The bracket 166 is connected to the upperend of the piston rod 90 with a fastener 168 for generally verticalmovement therewith. As depicted in FIGS. 2 and 3, the pulley 164 isdisposed within a space 170 defined by the frame members 134, 136, 138,and 140 on the sides, the upper spring support 122 on the bottom, andthe frame top plate 142 on the top. A cable 172 is connected to a cablefastening eyelet 174. The cable fastening eyelet 174 is attached to theframe top plate 142. The cable 172 extends from the cable fasteningeyelet 174, downward within the space 170 around the pulley 164, upwardthrough the space 170, through the central hole 144 in the frame topplate 142, and is fixed at its other end to the drive float 44. In theillustrated embodiment, where one end of the cable 172 are attached tothe top of the frame top plate 142, the upward movement of the pistonassembly 40 is approximately one half of the distance of the upwardmovement of the drive float 44 during operation. It is also noted thatthe framework 132 could be alternatively constructed without departingfrom the teachings of the present invention; so long as a fixedconnection is available for the one end of the cable 172 to be attachedto a portion of the framework 132 above the pulley 164 as the chamber 37expands and contracts with the pulley 164 connected to the pistonassembly 40 for travel therewith.

The operation of the wave powered pumping apparatus 22 should be evidentfrom the foregoing description. Initially, the wave powered pumpingapparatus 22 is placed in a body of water 26. In the illustratedembodiment, the anchor 42 is connected to the cylinder assembly 38 anddisposed on the bottom surface 28, while the drive float 44 is connectedto the piston assembly 40 and disposed on the top surface 30, asdepicted in FIGS. 2 and 3. As a passing wave 32 moves by the wavepowered pumping apparatus 22, the crest 34 of the wave 32 causes thedrive float 44 to rise up. The rising of the drive float 44 pulls thecable 172 upward, which shortens the length of the cable 172 in thespace 170 of the framework 132 of the tide compensating device 66. Asthe length of the cable 172 in the space 170 shortens, the pulley 164moves upward, pulling the piston assembly 40 upward, the upward movementof the piston assembly 40 being less than the upward movement of thedrive float 44.

As the piston assembly 40 moves upward from the position depicted inFIG. 3 to the position depicted in FIG. 4, the flexible flapper 108 ispressed against the piston rigid support plate 92, sealing the openings96. This upward movement of the piston assembly 40 pushes the fluid 46within the chamber 37 out of the compacting chamber 37 through theoutlet 48. Also as the piston assembly 40 moves upward from the positiondepicted in FIG. 3 to the position depicted in FIG. 4, the upper springsupport 122 moves upward through the slots 160 and 162 formed by theframe members 134, 136, 138, and 140. This upward movement of the upperspring support 122 causes the springs 128 and 130 to stretch, storingenergy to bias the piston in the downward position of FIG. 3.Additionally, as the piston assembly 40 moves upward from the positiondepicted in FIG. 3 to the position depicted in FIG. 4, the pressuregenerated by the fluid 46 being pushed out of the compacting chamber 37causes the directional pressure-activated seal 85 to bear radiallyinwardly against the piston rod 90 to prevent the fluid 46 from exitingthe chamber 37 through the central hole 78 in the cylinder top plate 76.Moreover, the pressure generated by the fluid 46 being pushed out of thecompacting chamber 37 causes the shiftable seal 82 to push upwardagainst the cylinder top plate 76 and thereby seal the plurality ofopenings 80 in the cylinder top plate 76 against fluid exit through thecylinder top plate 76.

As the passing wave 32 moves beyond the wave powered pumping apparatus22, the trough 36 of the wave 32 allows the drive float 44 to fall backdownward. The downward bias of the stretched springs 128 and 130 pullsthe upper spring support 122 downward through the slots 160 and 162,which also moves the piston assembly 40 downward from the positiondepicted in FIG. 4 to the position depicted in FIG. 3, with theintermediate downward moving position depicted in FIG. 7.

As the piston assembly 40 moves downward, the flexible flapper 108shifts and/or flexes upward relative to the piston rigid support plate92 and is held in place by the stopper 110. The shifting of the flexibleflapper 108 allows fluid 46 from the body of water 26 to flow throughthe openings 74 in the cylinder bottom plate 70, through the openings 96in the piston rigid support plate 92, around the shifted flexibleflapper 108, and into the expanding chamber 37 to reload the cylinderassembly 38 with additional fluid 46, as depicted in detail in FIG. 7.Also, as the piston assembly 40 moves downward, the pumped fluid isprevented from re-entering the chamber 37 by the check valve 84 in theconduit 50. Additionally, as the piston assembly 40 moves downward, thedirectional pressure-activated seal 85 is relaxed and imparts virtuallyno drag force axially upon the piston rod 90 as the piston rod 90 movesthrough the central hole 78 of the cylinder top plate 76 aligned withthe disposition of the seal directional pressure-activated 85, asdepicted in FIG. 10. When the piston assembly 40 returns to the downwardposition of FIG. 3, the upper spring support 122 rests on the cylindertop plate 76 to prevent further downward movement of the piston assembly40.

As another wave crest moves past the wave powered pumping apparatus 22to cause the drive float 44 to rise up, the wave powered pumpingapparatus 22 is in the reloaded condition, depicted in FIG. 3, and thepumping process described above is repeated. This repeated pumpingprocess continuously pumps fluid 46 into the reservoir 54 to generateelectricity, as described above.

With reference now to FIGS. 11 and 12, a second embodiment of a wavepowered pumping apparatus 222 is depicted, wherein a similar cylinderassembly 238 and piston assembly 240 are combined with an anchor 242 anda drive float 244. The wave powered pumping apparatus 222 is verysimilar to the wave powered pumping apparatus 22, with similarcomponents between the two being numbered in similar fashion, butdiffering by an order of two hundred. Therefore, for the sake ofbrevity, only the components unique to this alternative embodiment ofthe wave powered pumping apparatus 222 will be described in detail.

A tide compensating device 266 interconnects the drive float 244 and thepiston assembly 240 such that the amount of the upward movement of thepiston assembly 240 is approximately one quarter of the amount of upwardmovement of the drive float 244. A framework 332 extends around andabove the cylinder body 268 and is connected at the top with a frame topplate 342. A pulley 364 is disposed above the top of an upper springsupport 322 and is housed in a bracket 366. The bracket 366 is connectedto the upper end of a piston rod 290 with a fastener 368 for generallyvertical movement therewith. As depicted in FIGS. 11 and 12, the pulley364 is disposed within a space 370 defined by the framework 332 on thesides, the upper spring support 322 on the bottom, and the frame topplate 342 on the top. A second pulley 376 is disposed at the top of thespace 370 and is housed in a bracket 378 connected to the frame topplate 342 with a fastener 380 so as to not move vertically. A thirdpulley 382 is coaxial with the first pulley 364 and is housed in thesame bracket 366. A cable 372 is connected to a cable fastening eyelet374 connected to the frame top plate 342. The cable 372 extends from thecable fastening eyelet 374, downward within the space 370 and around thefirst pulley 364, upward though the space 370 and around the secondpulley 376, back downward through the space 370 and around the thirdpulley 382, back upward through the space 370 and through a central hole344 in the frame top plate 342, and is fixed at its other end to thedrive float 344.

Thus, the operation of the alternative embodiment of the wave poweredpumping apparatus 222 is also similar in many ways to the operationdescribed above for the wave powered pumping apparatus 22, with anexception. As a passing wave (not shown in detail) moves by the wavepowered pumping apparatus 222, a crest 234 of the wave causes the drivefloat 244 to rise up, pulling the cable 372 upward, and shortening thelength of the cable 372 in the space 370 of the framework 332 of thetide compensating device 266. As the length of the cable 372 in thespace 370 shortens, the first pulley 364 and the third pulley 382 moveupward, moving the piston assembly 240 upward also, with the amount ofthe upward movement of the piston assembly 240 being about one quarterof the amount of the upward movement of the drive float, as will bereadily understood by one of ordinary skill in the art upon review ofFIGS. 11 and 12.

With reference now to FIGS. 13 and 14, a third embodiment of a wavepowered pumping apparatus 422 is depicted, wherein a similar cylinderassembly 438 and piston assembly 440 are combined with an anchor 442 anda drive float 444 in the opposite configuration of apparatus 22, suchthat the piston assembly 440 is connected to the anchor 442 to restrictvertical movement thereof, and the cylinder assembly 438 is connected tothe drive float 444 for reciprocal upward movement about the pistonassembly 438. The cylinder assembly 438 and the piston assembly 440cooperatively define an expanding chamber 437, similar in many respectsto the chamber 37 disclosed above. It is noted that this configuration,wherein the piston assembly 438 is the anchored component, can improvepumping efficiency of the wave powered pumping apparatus 422. With theexception of the configuration of the anchored assembly comprising thepiston assembly 438 and the moveable assembly comprising the cylinderassembly 440, the wave powered pumping apparatus 422 is very similar tothe illustrated wave powered pumping apparatus 22, with similarcomponents between the two being numbered in similar fashion, butdiffering by an order of four hundred. Therefore, for the sake ofbrevity, only the components unique to this alternative embodiment ofthe wave powered pumping apparatus 422 will be described in detail.

A chain 486 connects the anchor 442 to a piston rod 490 at an eyeletfastener 488 to prevent upward movement thereof. A piston rigid supportplate 492 is fixed at the upper end of the piston rod 490 and includes aplurality of radially extending openings 496. A piston side seal 502 isattached in a similar manner as in the embodiment described above, butwith the opposite vertical orientation, such construction being readilyunderstood by one of ordinary skill in the art upon review of the abovedescription of FIGS. 2-10. A flexible flapper 508 and a stopper 510 arealso similarly disposed with the opposite vertical orientation to forman inlet check valve part of the piston assembly 440.

Also similar to the embodiment disclosed above, a cable 572 connects thedrive float 444 to the cylinder assembly 438 to provide upward movementthereof. The cylinder assembly includes a body 468 and a plate 476 atthe bottom end thereof. The plate 476 has a central hole 478 andradially extending openings 480 cooperating with a shiftable seal 482,similar in construction to the embodiment described above, but also withthe opposite vertical orientation, such construction being readilyunderstood by one of ordinary skill in the art upon review of the abovedescription of FIGS. 2-10.

The cylinder assembly 438 also includes a reload mechanism 514 to biasthe cylinder assembly 438 in the downward direction. The cylinder reloadmechanism 514 includes a first pulley 576, disposed above the top of thepiston rod 490, and a second pulley 578 disposed below the first pulley576. As depicted, the first pulley 576 is connected to the top of thecylinder assembly 438 and the second pulley 578 is housed in a bracket580 that is connected to the bottom of the cylinder assembly 438. Acable 582 is connected to the top of the piston rod 490 and extends upand around the first pulley 576, down and around the second pulley 578,and up to a submerged float 584. The submerged float 584 is configuredto provide an upward buoyant force that is less than the upward buoyantforce created by the drive float 444. The submerged float 584preferably, although not necessarily, provides an upward buoyant forcethat is approximately ten to twenty percent of the upward buoyant forcecreated by the drive float 444, such as by using a smaller float of thesame material for the submerged float 584 compared to the drive float444 or by using a different material, as will be understood by one ofordinary skill in the art. The submerged float 584 exerts the upwardbuoyant force that is transmitted through the cable to provide adownward bias on the cylinder assembly 438, as will be readilyunderstood by one of ordinary skill in the art.

The operation of this embodiment of the wave powered pumping apparatus422 is also similar in many ways to the operation described above forthe wave powered pumping apparatus 22, but with the cylinder assembly438 being upwardly moveable with the passing of a wave and the pistonassembly remaining fixed to the anchor 442. Other details of theoperation of this embodiment will be readily understood by one ofordinary skill in the art upon review of the above description regardingthe embodiment of FIGS. 2-10. In addition, it is noted that the wavepowered pumping apparatus 422 is depicted without a tide compensatingdevice similar to that of the embodiments previously described, althoughit will be readily appreciated by one of ordinary skill in the art thatit is clearly within the ambit of the present invention to incorporatesuch a device for use with this embodiment.

The preferred forms of the invention described above are to be used asillustration only, and should not be utilized in a limiting sense ininterpreting the scope of the present invention. Obvious modificationsto the exemplary embodiments, as hereinabove set forth, could be readilymade by those skilled in the art without departing from the spirit ofthe present invention.

The inventor hereby states his intent to rely on the Doctrine ofEquivalents to determine and access the reasonably fair scope of thepresent invention as pertains to any apparatus not materially departingfrom but outside the literal scope of the invention set forth in thefollowing claims.

1. An apparatus for pumping a fluid using the continuous rising andfalling wave action in a body of water, said apparatus comprising: acylinder assembly, a piston assembly operably coupled with the cylinderassembly to define an expandable chamber, a fluid inlet communicatingwith the chamber, and a fluid outlet communicating with the chamber,wherein fluid is drawn into the chamber through the inlet as the chamberexpands and fluid is pumped out of the chamber through the outlet as thechamber contracts; an anchor connected to an anchored one of saidcylinder and piston assemblies to position said anchored one of theassemblies below the surface of the body of water and to restrict upwardmovement of said anchored one of the assemblies; a drive float riding ontop of the body of water such that a rising wave lifts the drive floatupward and a falling wave lowers the drive float downward, said drivefloat being coupled to a relatively moveable one of said cylinder andpiston assemblies to move the same in an upward direction relative tothe anchored one of the assemblies in response to a rising wave liftingthe drive float, said piston and cylinder assemblies beinginterconnected so that the chamber contracts to, thereby pump fluid fromthe chamber through the outlet, during upward movement of the moveableone of the assemblies, and the chamber expands, to thereby draw fluidinto the chamber through the inlet, during downward movement of themoveable one of the assemblies; and a tide compensating deviceinterconnecting the drive float and moveable one of the assemblies insuch a manner that the amount of upward movement of the moveable one ofthe assemblies is relatively less than the amount of upward movement ofthe drive float in response to a rising wave lifting the drive float,said tide compensating device comprising a framework fixed to theanchored one of the assemblies, a flexible element interconnecting themoveable one of the assemblies and the drive float, and a firstrotatable member connected to the moveable one of the assemblies, saidflexible element extending from a fixed connection on the framework thatis spaced above the first rotatable member as the chamber expands andcontracts, said flexible element extending downwardly from the fixedconnection, around the first rotatable member, and up to the drivefloat, causing the moveable one of the assemblies to move upward adistance less than that moved by the drive float as a rising wave liftsthe drive float.
 2. The apparatus as claimed in claim 1; and a pumpreload mechanism operably coupled to the moveable one of the assembliesto yieldably bias the same in a downward direction relative to theanchored one of the assemblies so as to facilitate drawing of fluid intothe chamber in response to a falling wave permitting the drive float tolower.
 3. The apparatus as claimed in claim 2, said pump reloadmechanism comprising a spring, said spring extending generallyvertically between the assemblies such that, as the moveable one of theassemblies moves upward in response to the rising wave lifting the drivefloat, a downward return force of the spring bias is overcome by theupward force provided by the buoyancy of the drive float.
 4. Theapparatus as claimed in claim 3, said spring configured to provide saiddownward return force of approximately between ten and twenty percent ofthe upward force provided by the buoyancy of the drive float.
 5. Theapparatus as claimed in claim 1, said fixed connection on the frameworkbeing disposed such that the distance of the upward movement of themoveable one of the assemblies is approximately one half of the distanceof the upward movement of the drive float.
 6. The apparatus as claimedin claim 5, said first rotatable member comprising a pulley, saidflexible element comprising a cable configured to wrap around thepulley.
 7. The apparatus as claimed in claim 1, said tide compensatingdevice further including a second rotatable member connected to theframework so as to be positioned above the first rotatable member as thechamber expands and contracts, and a third rotatable member connected tothe moveable one of the assemblies, said flexible element extending fromthe fixed connection on the framework, down and around the firstrotatable member, up and around the second rotatable member, down andaround the third rotatable member, and up to the drive float.
 8. Theapparatus as claimed in claim 7, said fixed connection on the frameworkand said second rotatable member being disposed such that the distanceof the upward movement of the moveable one of the assemblies isapproximately one quarter of the distance of the upward movement of thedrive float.
 9. The apparatus as claimed in claim 8, said firstrotatable member and said third rotatable member being coaxial.
 10. Theapparatus as claimed in claim 1, said fluid inlet including a checkvalve permitting one-way fluid flow into the chamber through the inlet.11. The apparatus as claimed in claim 10, said fluid outlet including acheck valve permitting one-way fluid flow out of the chamber through theoutlet.
 12. The apparatus as claimed in claim 10, said piston assemblyincluding a rigid support plate having a chamber-defining surface thatdefines in part the chamber, said support plate presenting a pluralityof openings that permit fluid to pass through the support plate and intothe chamber, said piston assembly further including a generally fluidimpermeable cover shiftably disposed adjacent the support plate formovement into and out of a plate-sealing position, in which the platesealingly engages the chamber-defining surface and thereby preventsfluid flow through the plate, said support plate and cover cooperativelyforming the fluid inlet check valve.
 13. The apparatus as claimed inclaim 12, said piston assembly including a piston rod slidably coupledto the cylinder assembly to permit generally vertical relative movementtherebetween, said support plate being carried on the piston rod, saidcover being flexible and vertically moveable along the piston rod, saidpiston assembly including a stopper fixed to the piston rod adjacent thecover opposite the support plate so as to limit movement of the coveraway from the support plate.
 14. The apparatus as claimed in claim 13,said cylinder assembly including an alignment guide that defines in partthe chamber and a central pathway, said piston rod being slidablyreceived within the pathway, said alignment guide including apressure-activated seal around the pathway, said pressure-activated sealimparting approximately no drag against the piston rod when the moveableone of the assemblies moves downwardly, said pressure-activated sealbeing put under pressure against the piston rod as the moveable one ofthe assemblies moves upwardly to expel the fluid out of the cylinder,such pressure preventing fluid from exiting the chamber through thepathway.
 15. An apparatus for pumping a fluid using the continuousrising and falling wave action in a body of water, said apparatuscomprising: a cylinder assembly; a piston assembly operably coupled withthe cylinder assembly to define an expandable chamber, a fluid inletcommunicating with the chamber, and a fluid outlet communicating withthe chamber, wherein fluid is drawn into the chamber through the inletas the chamber expands and fluid is pumped out of the chamber throughthe outlet as the chamber contracts; an anchor connected to an anchoredone of said cylinder and piston assemblies to position said anchored oneof the assemblies below the surface of the body of water and to restrictupward movement of said anchored one of the assemblies; a drive floatriding on top of the body of water such that a rising wave lifts thedrive float upward and a falling wave lowers the drive float downward,said drive float being coupled to a relatively moveable one of saidcylinder and piston assemblies to move the same in an upward directionrelative to the anchored one of the assemblies in response to a risingwave lifting the drive float, said piston and cylinder assemblies beinginterconnected so that the chamber contracts, to thereby pump fluid fromthe chamber through the outlet, during upward movement of the moveableone of the assemblies, and the chamber expands, to thereby draw fluidinto the chamber through the inlet, during downward movement of themoveable one of the assemblies, said piston assembly including a pistonrod slidably coupled to the cylinder assembly to permit generallyvertical relative movement therebetween, said cylinder assemblyincluding an alignment guide that defines in part the chamber and acentral pathway, said piston rod being slidably received within thepathway, said alignment guide including a pressure-activated seal aroundthe pathway, said pressure-activated seal imparting approximately nodrag against the piston rod when the moveable one of the assembliesmoves downwardly, said pressure-activated seal being put under pressureagainst the piston rod as the moveable one of the assemblies movesupwardly to expel the fluid out of the cylinder, such pressurepreventing fluid from exiting the chamber through the pathway; and atide compensating device interconnecting the drive float and moveableone of the assemblies in such a manner that the amount of upwardmovement of the moveable one of the assemblies is relatively less thanthe amount of upward movement of the drive float in response to a risingwave lifting the drive float, said tide compensating device comprising aframework fixed to the anchored one of the assemblies, a flexibleelement interconnecting the moveable one of the assemblies and the drivefloat, and a first rotatable member connected to the moveable one of theassemblies, said flexible element extending from a fixed connection onthe framework that is spaced above the first rotatable member as thechamber expands and contracts, said flexible element extendingdownwardly from the fixed connection, around the first rotatable member,and up to the drive float, causing the moveable one of the assemblies tomove upward a distance less than that moved by the drive float as arising wave lifts the drive float.
 16. The apparatus as claimed in claim15; and a pump reload mechanism operably coupled to the moveable one ofthe assemblies to yieldably bias the same in a downward directionrelative to the anchored one of the assemblies so as to facilitatedrawing of fluid into the chamber in response to a falling wavepermitting the drive float to lower.
 17. An apparatus for pumping afluid using the continuous rising and falling wave action in a body ofwater, said apparatus comprising: a cylinder assembly; a piston assemblyoperably coupled with the cylinder assembly to define an expandablechamber, a fluid inlet communicating with the chamber, and a fluidoutlet communicating with the chamber, wherein fluid is drawn into thechamber through the inlet as the chamber expands and fluid is pumped outof the chamber through the outlet as the chamber contracts, said fluidinlet including a check valve permitting one-way fluid flow into thechamber through the inlet; an anchor connected to an anchored one ofsaid cylinder and piston assemblies to position said anchored one of theassemblies below the surface of the body of water and to restrict upwardmovement of said anchored one of the assemblies; a drive float riding ontop of the body of water such that a rising wave lifts the drive floatupward and a falling wave lowers the drive float downward, said drivefloat being coupled to a relatively moveable one of said cylinder andpiston assemblies to move the same in an upward direction relative tothe anchored one of the assemblies in response to a rising wave liftingthe drive float, said piston and cylinder assemblies beinginterconnected so that the chamber contracts, to thereby pump fluid fromthe chamber through the outlet, during upward movement of the moveableone of the assemblies, and the chamber expands, to thereby draw fluidinto the chamber through the inlet, during downward movement of themoveable one of the assemblies, said piston assembly including a rigidsupport plate having a chamber-defining surface that defines in part thechamber, said support plate presenting a plurality of openings thatpermit fluid to pass through the support plate and into the chamber,said piston assembly further including a generally fluid impermeablecover shiftably disposed adjacent the support plate for movement intoand out of a plate-sealing position, in which the plate sealinglyengages the chamber-defining surface and thereby prevents fluid flowthrough the plate, said support plate and cover cooperatively formingthe fluid inlet check valve; and a tide compensating deviceinterconnecting the drive float and moveable one of the assemblies insuch a manner that the amount of upward movement of the moveable one ofthe assemblies is relatively less than the amount of upward movement ofthe drive float in response to a rising wave lifting the drive float,said tide compensating device comprising a framework fixed to theanchored one of the assemblies, a flexible element interconnecting themoveable one of the assemblies and the drive float, and a firstrotatable member connected to the moveable one of the assemblies, saidflexible element extending from a fixed connection on the framework thatis spaced above the first rotatable member as the chamber expands andcontracts, said flexible element extending downwardly from the fixedconnection, around the first rotatable member, and up to the drivefloat, causing the moveable one of the assemblies to move upward adistance less than that moved by the drive float as a rising wave liftsthe drive float.
 18. The apparatus as claimed in claim 17; and saidpiston assembly including a piston rod slidably coupled to the cylinderassembly to permit generally vertical relative movement therebetween,said cylinder assembly including an alignment guide that defines in partthe chamber and a central pathway, said piston rod being slidablyreceived within the pathway, said alignment guide including apressure-activated seal around the pathway, said pressure-activated sealimparting approximately no drag against the piston rod when the moveableone of the assemblies moves downwardly, said pressure-activated sealbeing put under pressure against the piston rod as the moveable one ofthe assemblies moves upwardly to expel the fluid out of the cylinder,such pressure preventing fluid from exiting the chamber through thepathway.